[PULL 0/3] s390x fixes

[PULL 0/3] s390x fixes

[Thomas Huth]

 Hi Peter!

The following changes since commit 7f1cab9c628a798ae2607940993771e6300e9e00:

  Merge remote-tracking branch 'remotes/bonzini-gitlab/tags/for-upstream' into staging (2021-08-02 17:21:50 +0100)

are available in the Git repository at:

  https://gitlab.com/thuth/qemu.git tags/pull-request-2021-08-03

for you to fetch changes up to 50e36dd61652a4a4f2af245655ed3ca08ef0a3ed:

  tests/tcg: Test that compare-and-trap raises SIGFPE (2021-08-03 15:17:38 +0200)

----------------------------------------------------------------
* Fixes for SIGILL and SIGFPE of the s390x linux-user target

----------------------------------------------------------------
Ilya Leoshkevich (1):
      target/s390x: Fix SIGILL and SIGFPE psw.addr reporting

Jonathan Albrecht (2):
      linux-user/s390x: signal with SIGFPE on compare-and-trap
      tests/tcg: Test that compare-and-trap raises SIGFPE

 linux-user/s390x/cpu_loop.c     |  66 +++++++++++++++++---------
 tests/tcg/s390x/Makefile.target |   2 +-
 tests/tcg/s390x/trap.c          | 102 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 148 insertions(+), 22 deletions(-)
 create mode 100644 tests/tcg/s390x/trap.c

[PULL 1/3] target/s390x: Fix SIGILL and SIGFPE psw.addr reporting

[Thomas Huth]

From: Ilya Leoshkevich <iii@linux.ibm.com>

For SIGILL, SIGFPE and SIGTRAP the PSW must point after the
instruction, and at the instruction for other signals. Currently under
qemu-user for SIGFILL and SIGFPE it points at the instruction.

Fix by advancing psw.addr for these signals.

Co-developed-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Buglink: https://gitlab.com/qemu-project/qemu/-/issues/319
Message-Id: <20210705210434.45824-2-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 linux-user/s390x/cpu_loop.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/linux-user/s390x/cpu_loop.c b/linux-user/s390x/cpu_loop.c
index f2d1215fb1..22f2e89c62 100644
--- a/linux-user/s390x/cpu_loop.c
+++ b/linux-user/s390x/cpu_loop.c
@@ -64,7 +64,13 @@ void cpu_loop(CPUS390XState *env)
         case EXCP_DEBUG:
             sig = TARGET_SIGTRAP;
             n = TARGET_TRAP_BRKPT;
-            goto do_signal_pc;
+            /*
+             * For SIGTRAP the PSW must point after the instruction, which it
+             * already does thanks to s390x_tr_tb_stop(). si_addr doesn't need
+             * to be filled.
+             */
+            addr = 0;
+            goto do_signal;
         case EXCP_PGM:
             n = env->int_pgm_code;
             switch (n) {
@@ -132,6 +138,10 @@ void cpu_loop(CPUS390XState *env)
 
         do_signal_pc:
             addr = env->psw.addr;
+            /*
+             * For SIGILL and SIGFPE the PSW must point after the instruction.
+             */
+            env->psw.addr += env->int_pgm_ilen;
         do_signal:
             info.si_signo = sig;
             info.si_errno = 0;
-- 
2.27.0

[PULL 2/3] linux-user/s390x: signal with SIGFPE on compare-and-trap

[Thomas Huth]

From: Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com>

Currently when a compare-and-trap instruction is executed, qemu will
always raise a SIGILL signal. On real hardware, a SIGFPE is raised.

Change the PGM_DATA case in cpu_loop to follow the behavior in
linux kernel /arch/s390/kernel/traps.c.
 * Only raise SIGILL if DXC == 0
 * If DXC matches a non-simulated IEEE exception, raise SIGFPE with
   correct si_code
 * Raise SIGFPE with si_code == 0 for everything else

When applied on 20210705210434.45824-2-iii@linux.ibm.com, this fixes
crashes in the java jdk such as the linked bug.

Signed-off-by: Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Buglink: https://bugs.launchpad.net/qemu/+bug/1920913
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/319
Message-Id: <20210709160459.4962-2-jonathan.albrecht@linux.vnet.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 linux-user/s390x/cpu_loop.c | 54 +++++++++++++++++++++++--------------
 1 file changed, 34 insertions(+), 20 deletions(-)

diff --git a/linux-user/s390x/cpu_loop.c b/linux-user/s390x/cpu_loop.c
index 22f2e89c62..6a69a6dd26 100644
--- a/linux-user/s390x/cpu_loop.c
+++ b/linux-user/s390x/cpu_loop.c
@@ -25,6 +25,35 @@
 /* s390x masks the fault address it reports in si_addr for SIGSEGV and SIGBUS */
 #define S390X_FAIL_ADDR_MASK -4096LL
 
+static int get_pgm_data_si_code(int dxc_code)
+{
+    switch (dxc_code) {
+    /* Non-simulated IEEE exceptions */
+    case 0x80:
+        return TARGET_FPE_FLTINV;
+    case 0x40:
+        return TARGET_FPE_FLTDIV;
+    case 0x20:
+    case 0x28:
+    case 0x2c:
+        return TARGET_FPE_FLTOVF;
+    case 0x10:
+    case 0x18:
+    case 0x1c:
+        return TARGET_FPE_FLTUND;
+    case 0x08:
+    case 0x0c:
+        return TARGET_FPE_FLTRES;
+    }
+    /*
+     * Non-IEEE and simulated IEEE:
+     * Includes compare-and-trap, quantum exception, etc.
+     * Simulated IEEE are included here to match current
+     * s390x linux kernel.
+     */
+    return 0;
+}
+
 void cpu_loop(CPUS390XState *env)
 {
     CPUState *cs = env_cpu(env);
@@ -106,29 +135,14 @@ void cpu_loop(CPUS390XState *env)
 
             case PGM_DATA:
                 n = (env->fpc >> 8) & 0xff;
-                if (n == 0xff) {
-                    /* compare-and-trap */
+                if (n == 0) {
                     goto do_sigill_opn;
-                } else {
-                    /* An IEEE exception, simulated or otherwise.  */
-                    if (n & 0x80) {
-                        n = TARGET_FPE_FLTINV;
-                    } else if (n & 0x40) {
-                        n = TARGET_FPE_FLTDIV;
-                    } else if (n & 0x20) {
-                        n = TARGET_FPE_FLTOVF;
-                    } else if (n & 0x10) {
-                        n = TARGET_FPE_FLTUND;
-                    } else if (n & 0x08) {
-                        n = TARGET_FPE_FLTRES;
-                    } else {
-                        /* ??? Quantum exception; BFP, DFP error.  */
-                        goto do_sigill_opn;
-                    }
-                    sig = TARGET_SIGFPE;
-                    goto do_signal_pc;
                 }
 
+                sig = TARGET_SIGFPE;
+                n = get_pgm_data_si_code(n);
+                goto do_signal_pc;
+
             default:
                 fprintf(stderr, "Unhandled program exception: %#x\n", n);
                 cpu_dump_state(cs, stderr, 0);
-- 
2.27.0

[PULL 3/3] tests/tcg: Test that compare-and-trap raises SIGFPE

[Thomas Huth]

From: Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com>

Signed-off-by: Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com>
Message-Id: <20210709160459.4962-3-jonathan.albrecht@linux.vnet.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 tests/tcg/s390x/Makefile.target |   2 +-
 tests/tcg/s390x/trap.c          | 102 ++++++++++++++++++++++++++++++++
 2 files changed, 103 insertions(+), 1 deletion(-)
 create mode 100644 tests/tcg/s390x/trap.c

diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
index 5d3de1b27a..bd084c7840 100644
--- a/tests/tcg/s390x/Makefile.target
+++ b/tests/tcg/s390x/Makefile.target
@@ -8,4 +8,4 @@ TESTS+=exrl-trtr
 TESTS+=pack
 TESTS+=mvo
 TESTS+=mvc
-
+TESTS+=trap
diff --git a/tests/tcg/s390x/trap.c b/tests/tcg/s390x/trap.c
new file mode 100644
index 0000000000..d4c61c7f52
--- /dev/null
+++ b/tests/tcg/s390x/trap.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2021 IBM Corp.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <signal.h>
+
+static void error1(const char *filename, int line, const char *fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+    fprintf(stderr, "%s:%d: ", filename, line);
+    vfprintf(stderr, fmt, ap);
+    fprintf(stderr, "\n");
+    va_end(ap);
+    exit(1);
+}
+
+static int __chk_error(const char *filename, int line, int ret)
+{
+    if (ret < 0) {
+        error1(filename, line, "%m (ret=%d, errno=%d/%s)",
+               ret, errno, strerror(errno));
+    }
+    return ret;
+}
+
+#define error(fmt, ...) error1(__FILE__, __LINE__, fmt, ## __VA_ARGS__)
+
+#define chk_error(ret) __chk_error(__FILE__, __LINE__, (ret))
+
+int sigfpe_count;
+int sigill_count;
+
+static void sig_handler(int sig, siginfo_t *si, void *puc)
+{
+    if (sig == SIGFPE) {
+        if (si->si_code != 0) {
+            error("unexpected si_code: 0x%x != 0", si->si_code);
+        }
+        ++sigfpe_count;
+        return;
+    }
+
+    if (sig == SIGILL) {
+        ++sigill_count;
+        return;
+    }
+
+    error("unexpected signal 0x%x\n", sig);
+}
+
+int main(int argc, char **argv)
+{
+    sigfpe_count = sigill_count = 0;
+
+    struct sigaction act;
+
+    /* Set up SIG handler */
+    act.sa_sigaction = sig_handler;
+    sigemptyset(&act.sa_mask);
+    act.sa_flags = SA_SIGINFO;
+    chk_error(sigaction(SIGFPE, &act, NULL));
+    chk_error(sigaction(SIGILL, &act, NULL));
+
+    uint64_t z = 0x0ull;
+    uint64_t lz = 0xffffffffffffffffull;
+    asm volatile (
+        "lg %%r13,%[lz]\n"
+        "cgitne %%r13,0\n" /* SIGFPE */
+        "lg %%r13,%[z]\n"
+        "cgitne %%r13,0\n" /* no trap */
+        "nopr\n"
+        "lg %%r13,%[lz]\n"
+        "citne %%r13,0\n" /* SIGFPE */
+        "lg %%r13,%[z]\n"
+        "citne %%r13,0\n" /* no trap */
+        "nopr\n"
+        :
+        : [z] "m" (z), [lz] "m" (lz)
+        : "memory", "r13");
+
+    if (sigfpe_count != 2) {
+        error("unexpected SIGFPE count: %d != 2", sigfpe_count);
+    }
+    if (sigill_count != 0) {
+        error("unexpected SIGILL count: %d != 0", sigill_count);
+    }
+
+    printf("PASS\n");
+    return 0;
+}
-- 
2.27.0

Re: [PULL 0/3] s390x fixes

[Peter Maydell]

On Tue, 3 Aug 2021 at 15:25, Thomas Huth <thuth@redhat.com> wrote:
>
>  Hi Peter!
>
> The following changes since commit 7f1cab9c628a798ae2607940993771e6300e9e00:
>
>   Merge remote-tracking branch 'remotes/bonzini-gitlab/tags/for-upstream' into staging (2021-08-02 17:21:50 +0100)
>
> are available in the Git repository at:
>
>   https://gitlab.com/thuth/qemu.git tags/pull-request-2021-08-03
>
> for you to fetch changes up to 50e36dd61652a4a4f2af245655ed3ca08ef0a3ed:
>
>   tests/tcg: Test that compare-and-trap raises SIGFPE (2021-08-03 15:17:38 +0200)
>
> ----------------------------------------------------------------
> * Fixes for SIGILL and SIGFPE of the s390x linux-user target
>
> ----------------------------------------------------------------


Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/6.1
for any user-visible changes.

-- PMM

Re: [PULL 0/3] s390x fixes

[Peter Maydell]

On Wed, 20 Jul 2022 at 08:58, Thomas Huth <thuth@redhat.com> wrote:
>
>  Hi!
>
> The following changes since commit b8bb9bbf4695b89bbdca702a054db0a7a2c8ff2b:
>
>   Merge tag 'pull-ppc-20220718' of https://gitlab.com/danielhb/qemu into staging (2022-07-18 19:27:25 +0100)
>
> are available in the Git repository at:
>
>   https://gitlab.com/thuth/qemu.git tags/pull-request-2022-07-20
>
> for you to fetch changes up to 23f13e1986e2ed3a02b65c0bf376c8c61d04ae7a:
>
>   tests/tcg/s390x: test signed vfmin/vfmax (2022-07-19 12:49:56 +0200)
>
> ----------------------------------------------------------------
> * Fixes for s390x floating point vector instructions
>


Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/7.1
for any user-visible changes.

-- PMM

[PULL 0/3] s390x fixes

[Thomas Huth]

 Hi!

The following changes since commit b8bb9bbf4695b89bbdca702a054db0a7a2c8ff2b:

  Merge tag 'pull-ppc-20220718' of https://gitlab.com/danielhb/qemu into staging (2022-07-18 19:27:25 +0100)

are available in the Git repository at:

  https://gitlab.com/thuth/qemu.git tags/pull-request-2022-07-20

for you to fetch changes up to 23f13e1986e2ed3a02b65c0bf376c8c61d04ae7a:

  tests/tcg/s390x: test signed vfmin/vfmax (2022-07-19 12:49:56 +0200)

----------------------------------------------------------------
* Fixes for s390x floating point vector instructions

----------------------------------------------------------------
Ilya Leoshkevich (3):
      target/s390x: fix handling of zeroes in vfmin/vfmax
      target/s390x: fix NaN propagation rules
      tests/tcg/s390x: test signed vfmin/vfmax

 target/s390x/tcg/vec_fpu_helper.c |   4 +-
 tests/tcg/s390x/vfminmax.c        | 411 ++++++++++++++++++++++++++++++++++++++
 fpu/softfloat-specialize.c.inc    |   3 +-
 tests/tcg/s390x/Makefile.target   |   7 +
 4 files changed, 422 insertions(+), 3 deletions(-)
 create mode 100644 tests/tcg/s390x/vfminmax.c